Arsenic is a semi-metal,and lipid-soluble arsenic compounds are one of the widespread forms in the environment and food chain,but there is a lack of standards for lipid-soluble arsenic compounds,which is one of the bottlenecks in the current analytical detection and toxicological studies of organic arsenic.In this study,four saturated arsenic-containing hydrocarbons,AsHC 318,AsHC 332,AsHC 346,and AsHC 374(The number is relative molecular mass),were successfully synthesized in three steps by using dimethylarsinic acid,potassium iodide,sodium hydroxide,and four brominated alkanes(1-Bromotetradecane,1-bromopentadecane,1-bromohexadecane,and 1-bromooctadecane)as raw materials.The structures of these four saturated arsenic-containing hydrocarbons were characterized by proton nuclear magnetic resonance(1H NMR)spectroscopy,13C nuclear magnetic resonance(13C NMR)spectroscopy,and high-resolution mass spectrometry(HR-MS).The yields of the method were 8%-10%,and the synthesized compounds could be used in subsequent toxicity evaluation experiments to assess the toxic effects and mechanisms of action of arsenic-containing hydrocarbons.This study provided an effective method for synthesis of arsenic-containing hydrocarbons,enriching the synthesis methods of arsenic-containing hydrocarbons,and provided raw materials for the subsequent toxicological studies of arsenic-containing hydrocarbons.

AIM:To investigate the mechanism by which the Z-DNA-binding protein 1(ZBP1)/receptor-in-teracting protein kinase 1(RIPK1)/mixed lineage kinase domain-like protein(MLKL)pathway modulates the necroptosis of neurons in a mouse model of Alzheimer disease(AD).METHODS:Thirty mice were randomly divided into three groups:normal control(NC)group,APP/PS1 model(MOD)group,and necroptosis inhibitor necrostatin-1(Nec-1)group,each with 10 mice.The learning and memory capacities of mice were assessed using the Morris water maze assays.The pathological morphology of hippocampal tissue was examined based on the HE staining assay.The expression levels of tumor necrosis factor-α(TNF-α)and interleukin-10(IL-10)in serum samples were measured by ELISA.The phosphory-lation of amyloid precursor protein(APP),Tau protein and the expression levels of proteins related to the ZBP1/RIPK1/MLKL pathway in hippocampal tissue were measured by Western blot.Immunofluorescence analysis was performed to de-tect the positive expression of p-RIPK1,while the mRNA level of ZBP1 was measured by RT-qPCR.RESULTS:Com-pared with NC group,the escape latency of mice in the MOD group was significantly longer(P<0.05),the number of crossing platforms was reduced(P<0.05),and the arrangement of hippocampal neurons was disordered accompanied with nuclear condensation.The concentration of TNF-α in serum was increased,whereas the concentration level of IL-10 was decreased(P<0.05).The expression levels of APP,p-Ttau and ZBP1 proteins in the hippocampal tissue and the ratios of p-RIPK1/RIPK1,p-RIPK3/RIPK3 and p-MLKL/MLKL were significantly upregulated(P<0.05).Similarly,the positive expression level of p-RIPK1 and the mRNA level of ZBP1 in hippocampal tissue were significantly upregulated(P<0.05).Compared with the MOD group,the cognitive function of AD mice,pathological damage of hippocampal tissue,and the levels of TNF-α and IL-10 in serum were reversed in the Nec-1 group(P<0.05).Moreover,the Nec-1 treatment signifi-cantly downregulated the expression levels of the above proteins(P<0.05),and the positive expression of p-RIPK1 and the mRNA level of ZBP1 were significantly decreased(P<0.05).CONCLUSION:The ZBP1/RIPK1/MLKL pathway is involved in the occurrence of neuronal necroptosis and the pathological process of AD mice.Inhibition of this pathway sig-nificantly ameliorates cognitive dysfunction and neuroinflammatory responses in AD mice.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

AIM:To investigate the mechanism by which the Z-DNA-binding protein 1(ZBP1)/receptor-in-teracting protein kinase 1(RIPK1)/mixed lineage kinase domain-like protein(MLKL)pathway modulates the necroptosis of neurons in a mouse model of Alzheimer disease(AD).METHODS:Thirty mice were randomly divided into three groups:normal control(NC)group,APP/PS1 model(MOD)group,and necroptosis inhibitor necrostatin-1(Nec-1)group,each with 10 mice.The learning and memory capacities of mice were assessed using the Morris water maze assays.The pathological morphology of hippocampal tissue was examined based on the HE staining assay.The expression levels of tumor necrosis factor-α(TNF-α)and interleukin-10(IL-10)in serum samples were measured by ELISA.The phosphory-lation of amyloid precursor protein(APP),Tau protein and the expression levels of proteins related to the ZBP1/RIPK1/MLKL pathway in hippocampal tissue were measured by Western blot.Immunofluorescence analysis was performed to de-tect the positive expression of p-RIPK1,while the mRNA level of ZBP1 was measured by RT-qPCR.RESULTS:Com-pared with NC group,the escape latency of mice in the MOD group was significantly longer(P<0.05),the number of crossing platforms was reduced(P<0.05),and the arrangement of hippocampal neurons was disordered accompanied with nuclear condensation.The concentration of TNF-α in serum was increased,whereas the concentration level of IL-10 was decreased(P<0.05).The expression levels of APP,p-Ttau and ZBP1 proteins in the hippocampal tissue and the ratios of p-RIPK1/RIPK1,p-RIPK3/RIPK3 and p-MLKL/MLKL were significantly upregulated(P<0.05).Similarly,the positive expression level of p-RIPK1 and the mRNA level of ZBP1 in hippocampal tissue were significantly upregulated(P<0.05).Compared with the MOD group,the cognitive function of AD mice,pathological damage of hippocampal tissue,and the levels of TNF-α and IL-10 in serum were reversed in the Nec-1 group(P<0.05).Moreover,the Nec-1 treatment signifi-cantly downregulated the expression levels of the above proteins(P<0.05),and the positive expression of p-RIPK1 and the mRNA level of ZBP1 were significantly decreased(P<0.05).CONCLUSION:The ZBP1/RIPK1/MLKL pathway is involved in the occurrence of neuronal necroptosis and the pathological process of AD mice.Inhibition of this pathway sig-nificantly ameliorates cognitive dysfunction and neuroinflammatory responses in AD mice.

OBJECTIVE To investigate the effects and mechanism of Wenpi tongluo kaiqiao formula （WPTL） against neuronal necroptosis in Alzheimer’s disease （AD） mice based on the Z-DNA binding protein 1 （ZBP1）/mixed lineage kinase domain-like protein （MLKL） signaling pathway. METHODS Forty APP/PS1 transgenic AD mice were randomly divided into model group， WPTL low-dose （WPTL-L） group （10.4 g/kg， calculated by the raw medicine）， WPTL high-dose （WPTL-H） group （20.8 g/kg， calculated by the raw medicine） and donepezil hydrochloride group （3 mg/kg）， with 10 mice in each group； another 10 C57BL/6J mice were selected as normal control group. Intragastric administration， once a day， for 30 consecutive days. Twenty-four hours after the last administration， Morris water maze test was performed to evaluate learning and memory abilities； the pathological morphology of hippocampal tissues was observed； the serum levels of tumor necrosis factor-α （TNF-α） and interleukin-4 （IL-4） were determined； the expressions of amyloid precursor protein （APP）， Tau protein， and ZBP1/MLKL signaling pathway-related proteins in hippocampal tissues were detected； the positive expression of phosphorylated receptor-interacting protein kinase 3 （p-RIPK3） in the neurons of hippocampal tissues and mRNA expression of ZBP1 were measured in hippocampal tissues. RESULTS Compared with normal control group， the escape latency of mice in model group was prolonged significantly on day 3 to 5 （P＜0.05）， the times of crossing platform reduced significantly （P＜0.05）， and obvious pathological changes were observed in the hippocampal tissue. The level of TNF- α， the expressions of APP， p-Tau and ZBP1， the phosphorylation levels of RIPK1， RIPK3 and MLKL， the fluorescence intensity of p-RIPK3 as well as the mRNA expression of ZBP1 were significantly increased （P＜0.05）， while the serum level of IL-4 was decreased significantly （P＜0.05）. Compared with model group， above indexes were reversed significantly in administration groups （P＜0.05）， and pathological damage of hippocampal tissue was alleviated. CONCLUSIONS WPTL can inhibit the ZBP1/MLKL signaling pathway， reduce neuronal necroptosis in AD mice， and inhibit inflammatory responses， thereby improving learning and spatial memory abilities in AD mice.

During sudden outbreaks of major infectious diseases,traditional vaccine clinical trials often fail to deliver timely and meaningful outcomes.To address this,innovative trial designs are essential to accelerate or restructure the traditional three-phase clinical trial process while maintaining adherence to scientific principles of drug candidate safety and efficacy.This paper presents various innovative vaccine clinical trial designs and concepts,along with critical considerations for their application,to serve as a methodological reference for related research.Adaptive designs provide flexibility by dynamically adjusting trial parameters—such as dose selection,population stratification,and sample size reestimation—based on interim analysis results.Bayesian designs incorporate historical data and prior information,reducing sample size requirements.Master protocol designs enable the evaluation of multiple treatments or target populations within a unified framework,significantly improving efficiency.Additionally,real-world data(RWD),including electronic health records vaccination records and insurance claims,supports the creation of virtual control groups,addressing ethical concerns while enhancing trial feasibility.A hybrid design combining randomized controlled trials(RCTs)with RWD is also proposed to leverage the strengths of both methodologies.These innovative designs optimize the research process,accelerating vaccine development and regulatory approval.By integrating these approaches,robust evidence-based insights can be generated,advancing precision medicine goals and strengthening public health responses to emerging infectious diseases.